Free fatty acid (FFA) and ketone body turnover will be measured in intact alloxan-diabetic rats under various experimental conditions. FFA turnover will be measured when ketone body concentrations are increased by infusion of acetoacetate and/or 3-hydroxybutyrate. Ketone turnover will be measured when blood FFA concentrations are increased by the infusion of an oleic acid emulsion stabilized with albumin. Results from these experiments should yield information regarding the regulation of fatty acid catabolism in the absence of insulin.